Evaluating the Superiority of Balanced Nutrition Over Vaccination in Mitigating Infectious Bronchitis Impacts on Broilers

This study evaluated the impact of balanced diets and vaccinations in the first week of life on broilers' performance, mortality, intestinal health, and liver enzymes affected by the infectious bronchitis virus (IBV) during the finisher phase. 120-day-old Ross 308 broiler chicks were raised in 12 pens using a randomized design, divided into three groups with four replicates each. The treatments included unbalanced diets for both vaccinated and unvaccinated groups and a balanced corn and soybean meal diet. IBV-infected chickens were introduced to all groups for 2 to 3 days at 25 days of age. Results showed that a balanced diet significantly improved average body weight, weight gain, and feed intake (P<0.05) and decreased mortality rates after IBV exposure (P<0.05). It also enhanced carcass weight, increased the relative lengths of the duodenum, jejunum, and ileum, and improved intestinal villus height and surface area (P<0.05) while reducing crypt depth (P<0.05). Additionally, liver Alkaline phosphatase (ALP) and Alanine transaminase (ALT) levels significantly decreased (P<0.05). In conclusion, a balanced diet during the starter phase supports better growth, nutrient absorption, liver function, and immune development. This leads to improved health and reduced mortality from IBV, and it proves more effective than vaccination in combating the virus.